Fair Value Measurements (Tables)

3 Months Ended

Mar. 31, 2012

Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]

The following table discloses the carrying amount, estimated fair value, and level within the fair value hierarchy of certain financial instruments not disclosed in other notes to Questar's financial statements in this Quarterly Report on Form 10-Q:



	Hierarchy Level of Fair Value Estimates	Carrying Amount		Estimated Fair Value		Carrying Amount		Estimated Fair Value		Carrying Amount		Estimated Fair Value
		Mar. 31, 2012				Mar. 31, 2011				Dec. 31, 2011
		(in millions)
Financial assets
Cash and cash equivalents	1	$	8.1	$	8.1	$	—	$	—	$	11.6	$	11.6
Long-term investment	1	14.5		14.5		13.4		13.4		14.4		14.4
Financial liabilities
Checks outstanding in excess of cash balances	1	—		—		1.6		1.6		—		—
Short-term debt	1	129.0		129.0		86.0		86.0		219.0		219.0
Long-term debt, including current portion	2	1,083.8		1,219.4		1,080.5		1,159.2		1,084.5		1,223.4

Questar Gas [Member]

Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]

Fair Value, by Balance Sheet Grouping

The following table discloses the carrying amount, estimated fair value, and level within the fair value hierarchy of certain financial instruments not disclosed in other notes to Questar Gas's financial statements in this Quarterly Report on Form 10-Q:



	Hierarchy Level of Fair Value Estimates	Carrying Amount		Estimated Fair Value		Carrying Amount		Estimated Fair Value		Carrying Amount		Estimated Fair Value
		Mar. 31, 2012				Mar. 31, 2011				Dec. 31, 2011
		(in millions)
Financial assets
Cash and cash equivalents	1	$	4.5	$	4.5	$	0.4	$	0.4	$	5.0	$	5.0
Financial liabilities
Notes payable to Questar	1	66.4		66.4		64.1		64.1		142.7		142.7
Long-term debt, including current portion	2	368.0		438.6		370.0		417.0		368.0		445.4

Questar Pipeline [Member]

Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]

Fair Value, by Balance Sheet Grouping

The following table discloses the carrying amount, estimated fair value, and level within the fair value hierarchy of certain financial instruments not disclosed in other notes to Questar Pipeline's financial statements in this Quarterly Report on Form 10-Q:



	Hierarchy Level of Fair Value Estimates	Carrying Amount		Estimated Fair Value		Carrying Amount		Estimated Fair Value		Carrying Amount		Estimated Fair Value
		Mar. 31, 2012				Mar. 31, 2011				Dec. 31, 2011
		(in millions)
Financial assets
Cash and cash equivalents	1	$	4.6	$	4.6	$	0.9	$	0.9	$	3.4	$	3.4
Notes receivable from Questar	1	14.5		14.5		40.7		40.7		8.8		8.8
Financial liabilities
Long-term debt, including current portion	2	458.9		517.9		460.9		496.8		459.0		519.4

- Definition

Tabular disclosure of the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments, assets, and liabilities. Such certain disclosures about the financial instruments, assets, and liabilities include: (1) the fair value of the required items together with their carrying amounts (as appropriate) and (2) the methodology and assumptions used in developing such estimates of fair value.

+ References

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+ Details